Providing good light to a surgical site can be problematic. Not only can overhead lights be unwieldy, they can be both a source of glare and of shadows simultaneously, making it difficult to see the surgical site and the video monitors. Head lamps also cast shadows, for example, of a surgeon's hands or instruments, and are intrinsically heavy (or require cumbersome connections to external light or power sources.)
Small lamps and other light-emitting structures are unnecessarily costly and complicated. They typically require bulbs, light-emitting diodes, or fiber-optical elements, as well as a source of power which potentially becomes an electric shock risk to the patient. Not only do they have multiple connections and bulky fixtures that complicate surgery, they can be problematic sources of heat. Also, a light fixture that incorporates elements such as light bulbs into a complex structure requires significant manufacturing costs.
Moreover, any light source—whether overhead or localized—can cause glares and reflections that are blinding or distracting. Light that glares off of monitors interferes with the ability of medical staff to monitor a patient's vital signs and light reflecting from steel or mirrored surfaces and instruments can interfere with a surgeon's focus.